Vulnerability · Published Oct 8, 2026 · Assigned by GitHub_M
CVE-2026-107735SumatraPDF: `sumatrapdfrestrict.ini` never revokes any permission (fail-open policy initialization)
Medium 5.4
In plain English
A medium-severity security flaw in sumatrapdf from sumatrapdfreader. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 7% of all known vulnerabilities).
Official description
SumatraPDF is a multi-format reader for Windows. In 3.6.1 and earlier, InitializePolicies() starts the sumatrapdfrestrict.ini path with gPolicyRestrictions set to Perm::All and only ORs permission bits, so the INI file never revokes permissions. Deploying SumatraPDF with this INI file, including a malformed file or zero-valued permission settings, can silently bypass configured disk, network, printing, registry, clipboard, preference, and fullscreen restrictions. The -restrict command-line path works correctly and is not affected. No fixed version is available as of this review.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| sumatrapdfreader | sumatrapdf | <= 3.6.1 |
Weakness: CWE-636 · Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N